Get an RBG, which was recently bought out by Oregon, but there are 3 kinds:
1/2 hp w/ 8" wheel
1 hp w/ 10" wheel
1.5 hp w/ 12" wheel
And to me, those differences are HUGE (ehhh so is the price, but performance...)

I found one for $250 or $300 cash here around my town, slightly used but it's the 1.5hp model and I tell you, that thing beats the crap out of angle grinders. It really is nice, has a lamp you can angle about and you just slide the blade in and out and BLAM it's sharp at a correct and even angle every time.
I think we're talking 20 seconds a blade, maybe 30-45 for the worse off ones, but nothing like what the handheld grinder method used to take me.

Yeah, if you want the good one then don't settle for less, get the big'n and you'll likely never need to worry about even the grinding wheel for several years.

At times I have been tempted to buy the "rolls royce" of sharpeners - the manga-matic. But at $600+, I can't justify it for a small operation.

Had OK results with a hand grinder but recently switched to a $29.95 Harbor Freight belt sander that I read about on kniveforums.com. A custom knife maker suggested it. I use an 80 grit blue zirconia belt and attach a magnetic angle finder to the blade to ensure a 30% angle.

And whats best, you can also use it to sharpen your knives using finer grit belts.

It takes about a minute per mower blade

If a renowed custom knife maker suggests using it for the sharpest knife you ever had, it was a no brainer for me to realize it could provide a low cost effective solution for mower blades.

Bottom line - it works great and does a better job than any local sharpening service.

We used angle grinder at start but bought the oregon about 4 years ago and love it. simple big dings only take 3 min to get a good edge and even across the blade. cheap and simple in the long run. cost us 180 for the 1hp 10" one probably cost ya 250 now but the time saved is worth it.

Lawnsite "Chief of Security"Topsites-ism"With the Wb, I'll gladly pop a wheelie and let you see the spinning blades as I steer towards you,"Team Fluid Film
As quoted by fellow member or lawn god "Fareway"We had the throttle cranked and we roostered tailed out of there.